Elapsed step times for inference stage in Pipeline and FeatureUnion

[MezentsevIlya]

Reference Issues/PRs

#19291

What does this implement/fix? Explain your changes.

Hello!

I think possibility to print elapsed time for steps on inference stage can be useful. Previously it was possible only for fitting stage. Now when parameter verbose is greater than or equal to 10 logs will be printed for both fitting and inference stages.

[MezentsevIlya]

@thomasjpfan, hi!
Sorry for disturbing. I see your activity lately. Maybe you can help me :)
It's my first PR, and it's already one week old. Do I need to call someone to review it or just wait?

[thomasjpfan]

I think we need to discussion on the issue if we want to include this feature. I do not think we normally have printing during transform.

[MezentsevIlya]

I think we need to discussion on the issue if we want to include this feature. I do not think we normally have printing during transform.

I think It's can be useful if you want to estimate how long your pipeline will be transform 10/100/100000 elements.

[jnothman]

Without really considering the value of the feature, I wouldn't want verbosity in transform at least while we are printing to stdout (cf. #17439), since it might mess up scripting uses of stdout.

[glemaitre]

I think that it is better to look at the API for proper logging instead of adding some verbosity for the moment.
We can put on hold this PR.